-Ambroise Tardieu, 1855 (The full citation of the paper in which he made this assertion is: Tardieu A. Ann Hyg Pub et de med Legale (series II) 1855;(6):371-82. This paper is quoted in the paper “Petechial Hemorrhages - A review of Pathogenesis” by Frederick A. Jaffe. American Journal of Forensic Medicine and Pathology 15(3):203-207, 1994)

A common error is to attribute the petechiae to the rupture of capillaries, whereas they actually emanate from small venules - capillary bleeding would be invisible to the naked eye.

-Bernard Knight (Forensic Pathology, 2nd Edition, 1996, page 348)

(N.B. Note the contradiction between quotes 2 and 3 - both from contemporary books and journals. This is another important forensic controversy that is far from over. For other similar forensic controversies, see quotes on "Forensic Mythology" and "Hydrostatic Test". Interestingly, Bernard Knight, writing under the pseudonym of Bernard Picton in his book "Murder, Suicide or Accident - The Forensic Pathologist at Work", (Robert Hale & Company, London, 1971), has this to say on page 102: "The lining of the smallest blood vessels - the capillaries - is very sensitive to both increased pressure and oxygen lack. When these become deranged, the capillaries become fragile and burst at many points, causing small haemorrhages into the tissues, called 'petechiae'."
One would tend to believe that while Knight changed his view between 1971 and 1996, others stuck to the traditional view.)

Physical evidence can not be intimidated. It does not forget. It sits there and waits to be detected, preserved, evaluated, and explained.

-Herbert Leon Macdonell (Quoted at the opening page in his book “The Evidence never lies”)

Physical evidence does not get excited, like people do.

-Herbert Leon Macdonell (Quoted at the opening page in his book “The Evidence never lies”)

Wherever he steps, whatever he touches, whatever he leaves even unconsciously, will serve as silent witness against him. Not only his fingerprints or his footprints, but his hair, the fibers from his clothes, the glass he breaks, the tool marks he leaves, the paint he scratches, the blood or semen he deposits or collects - all of these and more bear mute witness against him. This is evidence that does not forget. It is not confused by the excitement of the moment. It is not absent because human witnesses are. It cannot perjure itself. It cannot be wholly absent. Only its interpretation can err. Only human failure to find it, study and understand it, can diminish its value.

Poison: Any substance which, when relatively small amounts are ingested, inhaled, or absorbed, or applied to, injected to, or developed within the body, has chemical action that may cause damage to structure or disturbance of function producing symptomology, illness or death.

Poison: Any substance which, when ingested, inhaled or absorbed, or when applied to, injected into, or developed within the body, in relatively small amounts, by its chemical action may cause damage to structure or disturbance of function.

Poison is any substance in relatively small quantities that can cause death or illness in living organisms by chemical action. The qualification “by chemical action”, is necessary because it rules out such effects as those produced by a small quantity of lead entering the body at high velocity.

-Scientific American

(N. B. It may be interesting to note that the usual fatal dose of a lead salt such as lead acetate is considered to be about 20 g. A lead bullet weighing 20 g can also kill a person, but in that case, the death would not be by chemical action, and thus lead in the second case, would not be supposed to kill as a poison!)

All substances are poisons. There is none, which is not. The right dose differentiates a poison and a remedy.

-Paracelsus (1495-1541), Swiss physician and Chemist

(N. B. There are several versions of this quote, which differ. This is understandable as this quote has been translated in English from a different language. The real quote in the original language is given in “Handbook of Pesticide Toxicology, Vol. 1 (Principles), page xxvii, 2nd Edition, Edited by Robert I. Krieger, (Academic Press, 2001)”. The quote -in German- goes like this, “Alle Ding sind Gift und nichts ohn Gift; alein die Dosis macht das ein Ding kein Gift ist”. Krieger in his Foreword goes on to say, “With the exception of E=mc2, perhaps no other single statement has wielded such force in establishing the popular notoriety and the professional stature of an individual in the history of science as the words just quoted”. This in itself appears a very fine quote to me!).

Other similar quotes attributed to him are

What is there that is not poison. All things are poison and nothing (is) without poison. Solely the dose determines that a thing is not a poison.)

-N.C. Fraser in “ Accidental poisoning deaths in British children 1958-77”. Br Med J 1980; 280: 1595-1598 (In a survey of deaths due to accidental poisoning in British children, out of 598 registered deaths over 20 years, Fraser found that only three were attributable to the ingestion of plant poisons!)

Having sniffed the dead man’s lips, I detected a slightly sour smell, and I came to the conclusion that he had poison forced upon him.

Poisons and medicines are oftentimes the same substance given with different intents.

-Peter Mere Latham

Passion (poison) often makes fools of clever men; sometimes even makes clever men of fools.

-La Rochefoucauld

I maintain that though you would often in the fifteenth century have heard the snobbish Roman say, in a would-be-off-hand tone, “I am dining with the Borgias tonight”, no Roman was ever able to say, “I dined last night with the Borgias.”

-“And Even Now”, Max Beerbohm

When you consider what a chance women have to poison their husbands, it’s a wonder there isn’t more of it done.

-Kim Hubbard

Most signs and symptoms associated with natural disease can be produced by some poison, and practically every sign and symptom observed in poisoning can be mimicked by those associated with natural diseases.

-The Merchant of Venice. III.i.69 (quoted on the front page in “Curare -Its history and usage” by K. Bryn Thomas, Pitman Medical Publishing Co. Ltd. London, 1964. I found this book while leisurely scanning the S.M.S. Medical College library at Jaipur on 14 June 2001, when I had gone there as a post-graduate examiner)

Revolted by the odious crime of homicide, the chemist’s aim is to perfect the means of establishing proof of poisoning so that the heinous crime will be brought to light and proved to the magistrate who must punish the criminal.

-“Traite de Poison”, M.J.B. Orfila (1814)

MARTHA: “Well, dear, for a gallon of elderberry wine, I take one teaspoonful of arsenic, and add a half a teaspoonful of strychnine, and then just a pinch of cyanide.

-“Arsenic and Old Lace” by Joseph Kasserling, New York Pocket Books, New York, NY, 1944 (quoted by John Harris Trestrail III in his book “Criminal Poisoning” on page 93. Also by Serita Deborah Stevens and Anne Klarner in their book “Deadly Doses - A writer’s guide to poisons”, Writer’s Digest Books, Ohio, 1990 on page 10)

If all those buried in our cemeteries who were poisoned could raise their hand, we would probably be shocked by the numbers!

-John Harris Trestrail III, in this book “Criminal Poisoning” on page 99

And yonder soft phial, the exquisite blue
Sure to taste sweetly - is that poison too?

It would be nice if someday, like Star Trek’s Dr. McCoy, we could pass a “Tricorder” over the body in question and thereby scan for over a million different chemical entities.

-John Harris Trestrail III, in this book “Criminal Poisoning” on page 71, stressing the fact that when an analytical result for toxicology comes negative, it does not necessarily mean that the specimen was free of all chemical substances. It only means that none of the substances tested for were present in detectable quantities.

Every death with no visible signs of trauma must be considered a poisoning until the facts prove otherwise.

-John Harris Trestrail III, in this book “Criminal Poisoning” on page 99

Doctors put drugs of which they know little, into our bodies of which they know less, to cure diseases of which they know nothing at all.

-A frantic call made by several Americans in September - October 1982 to poison centres, following unfortunate deaths of 7 people, who took Tylenol Capsules, which all turned out to be laced with cyanide. Such a panic spread among the Americans that many reported that their toothpaste smelt oddly or their antacids tasted strangely. Many pharmacists described this reaction as “Tylenol Syndrome”. (Taken from “Dunea G. Death over the Counter. British Medical Journal, Vol, 286, 15 January 1983, pages 211-212”. This incident is also reported in “Forensic Pharmacology - Medicines, Mayhem, and Malpractice” by R.E. Ferner, Oxford University Press, 1996, at page 15)

Now she's acquitted, she should tell us in the interests of science how she did it!

-Sir James Piaget, a distinguished Victorian surgeon, exhorting Adelaide Bartlett, when she was acquitted, to tell how she killed her husband by giving him chloroform (quoted in "Murder - What dunit" by J.H.H. Gaute & Robin Odell, at page 93)

Datura makes you hot as a hare, blind as a bat, dry as a bone, red as a beet and mad as a hen.

-H.G. Morton

And some of them ate plentifully of it, the effect of which was a very pleasant Comedy; for they turned natural Fools upon it for several Days. One would blow a Feather in the Air; another would dart straws at it with much fury; and another stark naked was sitting up in a Corner, like a Monkey grinning and making Mows at them; a Fourth would fondly kiss and paw his Companions, and sneer in their Faces with a Countenance more antik than any in a Dutch Droll.

-Robert Beverly, describing the condition of some soldiers who accidentally ate Datura stramonium (Jimson weed) leaves in their salad. This description appears in the book “History and Present State of Virginia”, Book 2 (1705 A.D.), p 24

-Mrs. Mary Elizabeth Wilson of Durham, who poisoned her two husbands with phophorus, jokingly at her wedding feast in 1958 (Quoted in “The Bedside Book of Murder” by Richard & Molly Whittington-Egan, at page 81)

We’ll murder them all amid laughter and merriment,
Except for a few we’ll take home to experiment.
My pulse will be quickenin’ with each drop of strychnine we feed to a pigeon.
(It just takes a smidgin!)
To poison a pigeon in the park.